Abstract

Localized plan view TEM samples have been prepared from silicon semiconductor wafers using the focused ion beam lift-out technique. Two different methods of sample preparation before FIB machining were found to be successful: mounting cleaved samples sandwiched together or adding silver paint and cleaving through paint and samples. The plan view technique offers site specific TEM capability from a horizontal section rather than a vertical cross section. The sections can be taken from any layer and can be angled if desired. Results have been obtained from metal layers in a semiconductor device structure. TEM micrographs of tungsten plug arrays show non-uniform barrier layer coverage and tungsten grain size across the via. Hundreds of plugs have been cut through in one sample, thereby offering statistical as well as specific structural information. Metal and polysilicon lines have been examined for grain size and uniformity in a single micrograph. Plan view samples from continuous metal layers can also be made.

@article{osti_21202349,
title = {Plan view TEM sample preparation using the focused ion beam lift-out technique},
author = {Stevie, F. A. and Irwin, R. B. and Brown, S. R. and Shofner, T. L. and Drown, J. L. and Giannuzzi, L. A.},
abstractNote = {Localized plan view TEM samples have been prepared from silicon semiconductor wafers using the focused ion beam lift-out technique. Two different methods of sample preparation before FIB machining were found to be successful: mounting cleaved samples sandwiched together or adding silver paint and cleaving through paint and samples. The plan view technique offers site specific TEM capability from a horizontal section rather than a vertical cross section. The sections can be taken from any layer and can be angled if desired. Results have been obtained from metal layers in a semiconductor device structure. TEM micrographs of tungsten plug arrays show non-uniform barrier layer coverage and tungsten grain size across the via. Hundreds of plugs have been cut through in one sample, thereby offering statistical as well as specific structural information. Metal and polysilicon lines have been examined for grain size and uniformity in a single micrograph. Plan view samples from continuous metal layers can also be made.},
doi = {10.1063/1.56881},
journal = {AIP Conference Proceedings},
number = 1,
volume = 449,
place = {United States},
year = {Tue Nov 24 00:00:00 EST 1998},
month = {Tue Nov 24 00:00:00 EST 1998}
}

Abstract Scanning transmission electron microscopy (STEM) allows atomic scale characterization of solid–solid interfaces, but has seen limited applications to solid–liquid interfaces due to the volatility of liquids in the microscope vacuum. Although cryo-electron microscopy is routinely used to characterize hydrated samples stabilized by rapid freezing, sample thinning is required to access the internal interfaces of thicker specimens. Here, we adapt cryo-focused ion beam (FIB) “lift-out,” a technique recently developed for biological specimens, to prepare intact internal solid–liquid interfaces for high-resolution structural and chemical analysis by cryo-STEM. To guide the milling process we introduce a label-freein situmethod of localizing subsurface structuresmore » in suitable materials by energy dispersive X-ray spectroscopy (EDX). Monte Carlo simulations are performed to evaluate the depth-probing capability of the technique, and show good qualitative agreement with experiment. We also detail procedures to produce homogeneously thin lamellae, which enable nanoscale structural, elemental, and chemical analysis of intact solid–liquid interfaces by analytical cryo-STEM. This work demonstrates the potential of cryo-FIB lift-out and cryo-STEM for understanding physical and chemical processes at solid–liquid interfaces.« less

We have developed a precise resistivity measurement system for quasi-one-dimensional nanomaterials using a focused ion beam. The system enables the resistivity of carbon nanocoils (CNCs) to be measured and its dependence on coil geometry to be elucidated. At room temperature, the resistivity of CNCs tended to increase with coil diameter, while that of artificially graphitized CNCs remained constant. These contrasting behaviors indicate coil-diameter-induced enhancement in structural disorder internal to CNCs. Low-temperature resistivity measurements performed on the CNCs revealed that electron transport through the helical axis is governed by the variable range hopping mechanism. The characteristic temperature in variable range hoppingmore » theory was found to systematically increase with coil diameter, which supports our theory that the population of sp{sup 2}-domains in CNCs decreases considerably with coil diameter.« less

We proposed a novel technique developed from focused ion beam (FIB) polishing for sample preparation of electron backscatter diffraction (EBSD) measurement. A low-angle incident gallium ion beam with a high acceleration voltage of 30 kV was used to eliminate the surface roughness of cross-sectioned microbumps resulting from mechanical polishing. This work demonstrates the application of the FIB polishing technique to solders for a high-quality sample preparation for EBSD measurement after mechanical polishing. - Highlights: Black-Right-Pointing-Pointer The novel FIB technique of sample preparation is fast, effective and low-cost. Black-Right-Pointing-Pointer It can enhance the process precision to the specific area of themore » sample. Black-Right-Pointing-Pointer It is convenient for analyzing the metallurgy of the microbump in 3DIC packaging. Black-Right-Pointing-Pointer The EBSD image quality can be enhanced by just using a common FIB instrument.« less

A recent emergence of a cross-beam scanning electron microscopy (SEM)/focused-ion-beam (FIB) system have given choice to fabricate cross-sectional transmission electron microscopy (TEM) specimen of thin film multilayer sample. A 300 layer pair thin film multilayer sample of W/B{sub 4}C was used to demonstrate the specimen lift-out technique in very short time as compared to conventional cross-sectional sample preparation technique. To get large area electron transparent sample, sample prepared by FIB is followed by Ar{sup +} ion polishing at 2 kV with grazing incident. The prepared cross-sectional sample was characterized by transmission electron microscope.